The invention pertains to a lower lid for a grand piano, and to a grand piano having a lower lid. More particularly, the invention pertains to a hinged lid, and to a grand piano having a hinged lower lid.
The primary sound radiating component of a grand piano is its soundboard. The soundboard is horizontally oriented within the piano""s case. The bottom of a conventional grand piano is open, so that sound can radiate downward from the soundboard directly to the surface on which the piano rests.
A conventional grand piano has a hinged cover (to be referred to herein as a xe2x80x9ctop lidxe2x80x9d) which can be raised into an open position. When the top lid is propped in its open position, sound radiating upward from the soundboard is reflected by the top lid toward the front side of the piano (the curved side of the piano, which is on the right side of a pianist facing the keyboard).
U.S. Pat. No. 4,211,142, issued to Conklin, discloses attachment of a large bottom panel below the soundboard of a grand piano to reflect sound propagating downward from the soundboard toward the rear side of the piano. Conklin""s panel reflects sound in the opposite direction than the top lid of the piano to which it is attached. Conklin suggests that the bottom panel can be convex so as to reflect sound toward the ends of the piano (toward the keyboard and away from the keyboard) as well as toward the rear side of the piano. Conklin""s bottom panel has hinges 22 along one edge, and Conklin teaches that the hinges can be attached to the piano case, or to brackets connected to the piano case, to enable the panel""s free edge to be raised by a cable or chain 25 slightly above floor level during transportation of the piano.
U.S. Pat. No. 2,138,669, issued to Tower, discloses a tone deflector for a grand piano, which consists of a set of slanting vanes 13 fixedly mounted to the piano case under the soundboard. Tower teaches that some or all of the vanes can be mounted in orientations for deflecting sound toward the piano""s rear side, and that some or all of the vanes can be mounted in orientations for deflecting sound toward the piano""s front side. However, Tower""s vanes are very small, and would not have sufficient surface area to project sound efficiently outward from the soundboard. The small size of Tower""s vanes would also prevent them from being oriented at the proper angle for projecting sound efficiently outward from the soundboard to typical target areas.
Until the present invention, however, it had not been proposed that a grand piano be provided with a hinged lower lid completely covering the bottom of the piano""s case when closed (to protect the soundboard and mute the piano""s sound). Nor had it been proposed until the present invention that such a lower lid be lowered into an open position to which it reinforces and focuses the projection of midrange sounds outward from the front of the piano.
The invention is a grand piano having a lower lid attached thereto by hinges, and a lid for attachment to the bottom of a grand piano. Preferably, the lid is sized and shaped to completely cover the bottom of the piano case when latched in a closed position. In its closed position, the lower lid protects the soundboard from damage (such as during transportation of the piano) and mutes the piano""s sound. Such muting action is desirable, for example, when the piano is used in small room (such as a practice room), or when the piano resides on an upper level of a multi-level building (such as an apartment house) where it is necessary to minimize projection of sound from the piano to lower levels of the building.
The lower lid of the invention is designed so that, when released from its closed position and pivoted downward into an open position, it will reflect sound from the soundboard outward from the front of the piano. Preferably, the angular orientation of the lower lid in its open position is chosen to reinforce and focus the projection of sound within a desired frequency range (for example, midrange sounds) to a desired target region.
Such optimal angular orientation can be determined experimentally. In one embodiment, the optimal lid orientation for reinforcing projection of midrange sounds is determined as follows. A light beam (which can be a laser beam) is directed downward from the midpoint of the soundboard to a flat mirror which rests flat against the open lower lid, while the angle of the open lower lid is varied until the light beam reflects from the mirror to the desired target region (which can be, for example, a particular seat or row of seats in a concert hall). To reinforce projection of non-midrange sounds, the light beam should be directed downward from a point on the soundboard other than the midpoint.
In one embodiment, the lower lid of the invention consists of two or more panels connected together by hinges. In this embodiment, the lower lid can be detached from the piano and folded into a compact volume for convenient handling and storage. The dimensions of the lid, and the positions of hinges which connect its component panels, are preferably predetermined so that lid has an optimal orientation for reinforcing projection of midrange sounds in a typically-sized room or concert hall, when the lid is lowered to an open position in which it rests on the floor.
The lower lid of the invention can be fitted with one or more removable sound-absorbing pads (composed of styrofoam or another sound-absorbing material). Such pads will enhance the muting action of the lower lid in its closed position, and can be removed when the lid is lowered into its open position.